Firefox and IE Already Support Clearing Flash Cookies

Clearing Flash LSOs to be supported in all major browsers

The next major version of Flash Player, which is currently in beta stage, will leverage APIs already supported in Mozilla Firefox and Internet Explorer to allow clearing Flash Local Shared Objects (LSOs) directly from inside the browsers.

LSOs are containers where Flash applications can store various pieces of information, like settings or the cache. Because they can also serve the same purpose as HTTP cookies, they are commonly referred to as Flash cookies.

One of the major problems with LSOs is that clearing them is a complicated process that involves users interacting with a special page on Adobe's site.

Because of this obscurity, LSOs are being abused not only to track visitors, but also to re-spawn HTTP cookies they intentionally deleted.

In order to make it easier for users to avoid this kind of tracking, Adobe has integrated Flash Player 10.3 with the browser interfaces used to delete history, HTTP cookies and other data.

This is achieved by levering application programming interfaces specifically exposed by browsers for this purpose.

Google recently announced that the latest Chrome development build has support for such an API called ClearSiteData, however, the Mozilla Firefox supports it from version 4. Meanwhile, IE8 and IE9 also have their own APIs designed for this purpose.

"Flash Player 10.3 integrates control of local storage with the browser’s privacy settings in Mozilla Firefox 4, Microsoft Internet Explorer 8 and higher, and future releases of Apple Safari and Google Chrome," Adobe announced.

Andy Zeigler, Microsoft's program manager for Internet Explorer, welcomed the change and noted that "it resolves a longstanding privacy issue." He failed, however, to mention that Silverlight, which serves pretty much the same purpose as Flash, has a similar hard to clear storage location.

"Microsoft is considering adding this capability to Silverlight but we have nothing to share at this time," a Microsoft spokeswoman told The Register when asked about plans to offer similar browser control for the technology.